Security devices, such as for example, padlocks and other types of conventional locks are known in the art. Many security devices are provided for restricting access to equipment and control instruments, including, for example, electrical components, such as switches, dials and push buttons, and fluid system components, such as valves and pressure regulators. Industrial and commercial equipment are often provided with a lockout feature (e.g., a locking bracket or similar structure) to facilitate the restriction of access to, or lockout of, the equipment. The equipment's lockout feature typically includes a hasp or other such apertured member or members configured to receive a shackle (or cable or other retaining member) of a lock to prevent movement of the apertured member with respect to another portion of the lockout feature, thereby preventing access to, or operation of, the equipment.
In some applications, it may be desirable to require the authorization of multiple technicians or other authorized personnel to allow access to, or operation of, a locked out piece of equipment. While a piece of equipment's lockout feature may be sized to retain multiple locks, a safety lockout hasp may instead be provided to be secured to the apertured member. A conventional safety lockout hasp includes a shackle to be secured to the equipment's lockout feature, and one or more apertures for receiving shackles (or other lockable retaining members) of one or more locks. Each of the inserted lockable retaining members prevents withdrawal of the shackle from the equipment's lockout feature, thereby requiring removal of all of the lockable retaining members from the safety lockout hasp to remove the lockout hasp from the equipment's lockout feature to allow access to, or operation of, the equipment.
FIGS. 1 and 2 illustrate a conventional safety lockout hasp 20 including first and second clasp members 21a, 21b hingedly secured to a shackle member 25 and retained on the shackle by a flanged end 24 and a retaining ring 26. The clasp members 21a, 21b are rotatable about the shackle 25 between a closed position (FIG. 1) and an open position (FIG. 2). In the closed position, apertures 27a, 27b of the first and second clasp members 21a, 21b align to receive lockable retaining members of one or more locks (not shown), thereby securing the clasp members in a closed position relative to the shackle 25. Insertion of one or more lockable retaining members through the aligned apertures 27a, 27b prevents rotation of the clasp members 21a, 21b to the open position for removal of the lockout hasp 20 from the lockout feature.
Depending on the size of the lockable retaining members used with the safety lockout hasp 20 of FIGS. 1 and 2, the clasp members 21a, 21b may be slightly rotatable with respect to the shackle 25 even when one or more locks are secured through the aligned apertures 27a, 27b. 